Jack.



J. MOSIMAN.

JACK. APPLIQATION P'ILBD JUNE 4, 1910.

Patented Aug. 23, 1910.

ew.' u n/MW @iwi/@m5 @5w V MW Y 'Il c ,I SMM/M1 JOHN IVIOSIMAN, 0F SEDALIA, MISSOURI.

J ACK.

Specication of Letters Patent. Patented Aug, 23, 19110.

Application led June 4, 1910. Serial No. 565,103.

To all whom it may concern:

Be it known that I, JOHN MosrMAN, citizen of the United States, residing at Seda-- lia, in the county of Pettis and State of Missouri, have invented a new and useful Jack, of which the following is a specification.

This invention relates to improvements in jacks, and has special reference to a jack to be used as a support for scaffolding.

One object of the invention is to provide a jack which may be set up close to a wall and readily adjusted to support a scaffold or platform at any desired height and which will be provided with simple and efficient means for preventing the dropping of the scaffold when the jack has been adjusted to that height.

A further object of the invention is to provide a construction which will permit the several parts to be readily arranged in a small compass when the jack is to be shipped from the factory and to be as readily assembled when it is to be set up for use.

All these objects, and such other objects as will incidentally appear hereinafter, are attained in the use of the device illustrated in the accompanying drawings, and the invention consists in certain novel featuresvof the same which will be hereinafter` first fully described and then particularly pointed out in the appended claims.

In the drawings,fFigure 1 is a perspective view of a jack embodying my improvements. Fig. 2 is a central vertical section of the same. Fig. 3 is a horizontal section taken on the line 3 3 of Fig.2. Fig. 4 is a detail perspective view of the bracket by which the supporting foot or step is carried.

In carrying out my invention, I employ a hollow standard which is provided with a slightly enlarged and ornamental base 1 which is adapted to rest upon the ground or upon the floor of a room in which the scaffolding is to be used. The standard is composed of a back plate 2, rising from the base, and spaced guides 3 secured to the front side of the standard and connected at their upper ends by a strap or cross bar 4. The guides 3 are provided with longitudinal grooves or recesses 5 in their inner opposed faces, and the back plate 2 is provided with a longitudinal slot 6, as clearly shown. To the guides 3, at and near the lower ends of the same, I secure the braces or lugs 7 which have forkedinner endssecured to the sides of the guides, and extend outward and downward therefrom, as clearly shown. A central leg 8 is provided with branches 9, at its inner end, which are secured to the front sides of the guides 3, and the outer lower extremities of all the legs are formed in'tegral with or secured rigidly to a foot or rim 10 which is arranged in the same plane as the under side of the base l so as to provide an extended support or rest by which the standard will be held in an upright position. By having the inner ends of the side legs 7 forked, as illustrated, a more extended-bearing against the sides of the standard is obtained, and by having the front leg 8 branched, as shown, I obtain an extended bearing at each side of the standard and also enable the leg to clear the step and the locking plates, as will presently appear. On the rear side of the backplate 2, adjacent the longitudinal slot 6 therein, I provide the off-sets or bearings 1l in which an operat-i ing shaft 12 is journaled, said shaft being provided with a crank handle 13 at one end. Intermediate its ends, a gear wheel 14 is secured to the operating shaft, and this 'gear wheel plays in the slot 6, as clearly shown in Fig. 2.

To the inner opposed faces of the guides 3, in advance of the vertical longitudinal grooves or seats 5 therein, I secure the supporting plates 15 which are provided along their front edges with forwardly projecting shoulders 16 having notches 17 in their upper sides, as clearly shown. A lifting bar 18 is mounted between the guides 3 and is provided with longitudinal ribs 19 on its sides engaging the grooves 5 in the guides and has its main portion extending into and filling the space between the guides, as clearly shown. In the rear side of this lifting bar is provided a longitudinal vertical groove 20, while seated in the rear side of the bar is a plate 21 having a series of openings 22 formed therein, the said openings being engaged by the teeth of the gear wheel 14, as clearly shown in Fig. 2, so that the rotation of the said gear wheel will act upon the plate 21 to raise or lower the lifting bar, as will be readily understood.

Near the lower end of the lifting bar, in the front side of the same, is a recess adapted to receive the upper hooked end 23 of a bracket 24 which is provided near its upper hookedend with aforwardly extending horizontal lug 25 and near its lower end u shown clearly in Figs. 2 and 4. Below the lug 26 an opening'27 is provided in the bracket through which a screw or similar fastening device 28 is inserted into the lifting bar to secure the bracket thereto. A step 29 is secured to the lug 25 and projects forwardly therefrom and has its outer end supported by a brace 30 secured to the lug 26 and extending up to the step, as clearly shown, whereby the outer end of the step will be prevented from dropping under the weight imposed thereon in the use of the jack. A holding pin 31 is secured to the step 29 by a cord or other flexible connection 32, and this pin is adapted to be inserted through the open space below the step and engage the notches 17 in the shoulder 16 so as to prevent the dropping of the lifting bai' after the same has been adjusted to the desired height. In order to prevent the lifting bar being raised to such a point that the rack plate 21 will not properly mesh with the teeth of the gear wheel 14, I provide a stop 33 in the front side of the lifting bar above the step 29 which is adapted to impinge against the strap or cross bar 4 and thereby arrest the upward movement of the lifting bar, as will be readily understood.

From the foregoing description, the use and advantages of my device will be readily appreciated. One of the jacks will be provided at each corner of the scaffold or platform, and the said scaffold or platform will be placed upon a cross bar having its ends resting upon the steps 29 of the jacks at one end of the scaffold. This arrangement will permit the ends of the scaffold to extend somewhat between the standards of the jacks so that the jacks will aid in preventing lateral movement of the scaffold, but the corners of the scaffold may be placed directly upon the steps 29 and the cross bars dispensed with. The jack is adjusted to support the scaffold at the desired height by rotating the operating shaft 12 which will thereby act through the gear wheel 14 and the rack plate 21 to raise the lifting bar and bring the step 29 to the desired height. inserted through the triangular space provided by the step 2-9, t-he brace 30 and the lifting bar so as to engage the notches 17` immediately below the step and thereby prevent the lowering of the step and the lifting bar under the weight placed thereon through the platform. or scaffold. lhen it is desired to lower the platform, the holding pins 31 are removed and the scaffold then permitted to descend, as will be understood. S extend laterally beyond the locking and supporting plates 15, and the body of the leg terminates at such a point in advance of the standard as will permit the brace 30 The holding pin 31 is thenv The branches of the front leg to descend to the full limit of movement of the lifting bar so that the step 29 will not be forced to remain in an elevated position when it is desired to remove the scaffold. rIhe removal of the stop 33 or the fastening screws by which the cross bar or strap 4 are secured to the upper ends of the guides 3 will permit the lifting bar to be raised entirely from the standard, and the step may then be readily removed from the lifting bar by merely disengaging the fastening 2S and then shifting the bracket 24 laterally so as to move its upper hooked end 23 out of engagement with the angular groove or seat in the front side of the lifting bar. The device can then be placed within a small space for transportation by removing the supporting legs and disengaging the operating shaft and driving wheel which will require but a few minutes time and is a very simple operation. The step may be formed integral with the bracket to which it is secured, but as a wooden step and brace will be lighter, I prefer to employ the construction illustrated in the drawings.

Vhile I have described the principle of operation of the invention, together with the apparatus which I' now consider to be the best embodiment thereof, I desire to have it understood that the apparatus shown is merely illustrative, and that suchchanges may be made when desired as are within the scope of the claims appended hereto.

Having thus described my invention, what I claim is:-

1. In a jack, the combination of a slotted standard, a lifting bar mounted therein, a pair of supporting plates secured in the slotted standard and projecting forwardly therefrom and having a series of notches alongtheir front edges, an open step carried by the lifting bar, and a holdingpin adapted to be inserted' through the said step to engage the notchesy in the supporting plates and thereby lock the lifting bar and step at any desired height.

2. In a jack, the combination of a standard, a lifting bar mounted therein, a bracket removably secured to the lower endv of the said standard, a step carried by theV said bracket, and means for engaging the step and the standard to lock the step at any desired height of the standard.

3. In a jack, the combination of a standard, a lifting bar mounted therein and provided with an angular recess in its front side, a bracket bearing against the front side of the standard and provided with a. hooked fupper endY fitting in said recess, a step carried by said bracket, means for raising the lifting bar, and means for holding the bar in its raised position.

4. In a jack, the combination of a standyard s aced Guides thereon a lifting bar 7 D 23 fitting between said guides and provided in its outer face with a transverse recess the ends of which are closed by the guides, a bracket bearing against the front side of the standard and provided with a hooked upper end tting in said recess, a step carried by said bracket, means for raising the lifting bar, and means for holding the bar in its raised position.

5. In a jack, the combination of a standard, spaced guides thereon, supporting plates projecting from the guides and provided along their projecting edges with notched horizontal shoulders, a lifting bar fitting between the guides and provided in its front face with a transverse recess, a bracket having a hooked upper end engaging said recess and having its lower end removably secured to the lifting bar, a step carried by said bracket, means for raising the lifting bar, and a holding pin adapted to engage the notched shoulders on the sup orting plates below the step to hold the llifting bar in the raised position.

6. In a jack, the standard comprising a back plate, a base, and connected and spaced guides, the latter being grooved vertically and the back plate having a lon itudinal slot, in combination with the pair o vertical supporting plates rigidly secured to the guides and provided with forwardly projecting shoulders, a lifting bar mounted between the guides in advance of the back plate and provided with longitudinal ribs engaging the grooves of the guides, a shaft mounted in rear of the back plate and carrying a pinion, a plate secured to the rear side of the lifting bar and provided with openings engaged by the teeth of the pinion, a step carried by the lifting bar and having means for engaging the shoulders on the supporting plates, and means for driving the said shaft. Y In testimony, that I claim the foregoing as my own, I have hereto affixed my signature in the presence of two witnesses.

JOHN MOSIMAN. Witnesses:

W. H. REYNOLDS, E. E. MAY. 

